10 Most Powerful Beings Venom Has Defeated
5. Spider-Man - ASM #375

As any shonen anime fan will tell you, the best way to show that your new bad guy is the toughest around is to have him toss the biggest baddest guy in the room like a salad, and seeing as how his name is on the front of the comic, makes sense that the sacrificial lamb would be Spider-Man.
The first time these two went head to head in Amazing Spider-Man #375 is one of the all time great one-sided fights in all of comics. When Venom goads Spidey into a fight by kidnapping his resurrected parents, there is just nothing the wall crawler can do to put up a fight against the symbiote, who takes him apart in a brutal manner readers had never seen before up to that point.
Sure, Spidey had lost plenty of times before, but rarely so thoroughly, and so brutally. Culminating in Venom grabbing Spider-Man by the head and pounding it into the concrete base of a roller coaster until the entire thing collapsed on top of them.
A horrifying showcase of Spidey's new arch enemy, no wonder this dude stuck around after an intro like that.